As the pound sterling lost 12 per cent to hit the 31-year low, the Thai baht lost 0.6 per cent in the morning to Bt35.40 per US dollar. Singapore dollar was 1.5 per cent lower to 1.3580; Malaysian ringgit 2.3 per cent lower to 4.1120; and Indonesian rupiah 1.2 per cent to 13,425.
To United Overseas Bank, the fall in Asean currencies are well within expectation. It earlier anticipated 2-3 per cent depreciation in the Brexit scenario.
Against US dollar, the euro fell 3.2 per cent to 1.1020. The Japanese yen, a safe haven currency, soared over 6.7 per cent to almost 99 yen per dollar.
The sterling has crashed close to 12 per cent, to a low of 1.3225/30 from high of 1.5022 earlier this morning, the lowest level since 1985. Looking further out, UOB expects the sterling to remain under pressure and decline further to the mid-1.20s by the end of third quarter.
Standard & Poor's Ratings Services warned earlier that the UK could lose its "AAA" credit rating following the fallout from the EU referendum results.